As is known in the art, color separation scanners process negative and positive slides in different ways. Therefore, prior art scanners require some indication from the operator as to whether the input medium to be scanned is a positive or negative slide. Example methods of providing indications are via a specific button or mechanical switch, or selecting from a menu on a screen.
The requirement of repeated indication can be irritating, troublesome and can cause time consuming mistakes, especially with scanners which automatically load input media to be scanned.